Door check



L. .1. GIBSON Dec. 17, 1968 DOOR CHECK Filed May 18, 1967 FIG.

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. INVENTOR LOUIS J. GIBSON FIG.7.

invention comprises a control United States Patent 3,416,182 DOOR CHECK Louis J. Gibson, 1014 Anna Road, Huntiugdon Valley, Pa. 19006 Filed May 18, 1967, Ser. No. 639,510 10 Claims. (Cl. 1652) ABSTRACT OF THE DISCLOSURE A door check for outside doors such as storm and screen doors constructed to provide a substantial delay in the closing of an opened door to allow time for a person to pass through the doorway without the necessity for holdin g the door open manually.

Background of the invention The invention relates to a door check for outside doors comprising means for holding the door open against the closing action of the usual spring means biasing the door to the closed position.

The door checks of the prior art usually comprise a cylinder having one end secured to the door, a piston mounted for movement within the cylinder, a piston rod extending from the piston through the end of the cylinder for connection to the door frame at an appropriate location, and a spring arranged to bias the piston and cylinder so that the door is urged toward the closed position. There is also provided some means to regulate the rate at which the door is closed after it has been moved to an opened position.

A problem with the prior art devices is that they are incapable of producing a very long delay such as would be necessary to permit a person to carry packages or other articles through the doorway without the necessity for holding the door opened manually. The door check in accordance with this invention provides a solution to this problem.

Summary of the invention Briefly stated, the door check in accordance with the means within the cylinder for effecting a delay in addition to the normal delay provided by the piston, this means being effective after the door has been opened beyond a predetermined amount. Moreover, this means is effective to provide a greater delay as the door is opened farther. By the arrangement in accordance with the invention, the above-discussed problem of providing a long delay is solved.

Brief description of the drawings FIGURE 1 is an axial section of a preferred embodiment of the invention;

FIGURE 2 is a fragmentary sectional view showing the piston means in accordance with the invention in one condition during an opening movement of the door;

FIGURE 3 is a fragmentary sectional view showing the piston means in accordance with the invention in another condition during an opening movement of the door;

FIGURE 4 is a fragmentary elevational view of a door frame and door with the door check in accordance with the invention mounted thereon;

FIGURE 5 is a schematic view of a door check in accordance with the invention illustrating the position of the parts when the door is closed;

FIGURE 6 is a schematic view of a door check in accordance with the invention illustrating the position of the parts when the door is partly open; and

FIGURE 7 is a schematic view of a door check in ac cordance with the invention illustrating the position of the parts when the door is fully open.

Description of the preferred embodiment The door check disclosed in the drawing comprises a cylinder 10 threadedly secured at each end into a pair of cylinder heads 12 and 14 as shown in FIGURE 1. The cylinder 10 and the cylinder heads 12 and 14 cooperate to define a cylindrical chamber 15 which is filled with a fluid such as oil. The cylinder head 14 closes one end of the cylinder 10 and is provided with a projection 16 having a bore therein for use in mounting the door check. Cylinder head 12 is provided with a central opening 18 through which a piston rod may extend as will be described hereafter.

A piston head, indicated generally at 20, is mounted within cylinder 10 for axial reciprocating movement relative thereto. The piston head 20 is mounted on a reduced diameter portion 22 at one end of a piston rod 24 which extends therefrom along the longitudinal axis of cylinder 10 and through the central opening 18 in cylinder head 12. The end 26 of piston rod 24 which is externally of the chamber 15 is formed in a flattened configuration and is provided with a bore therein for use in the mounting of the door check. A suitable seal 27 is provided between opening 18 and piston rod 24.

The piston head 20 is made of a plurality of washerlike members including a pair of metallic washers 30 and 32 providing annular recess 34 at their periphery for receiving an annular packing ring 36 of a suitable rubber or composition material. Adjacent the washer 32 is a metallic backing washer 38 and adjacent the latter is a flexible heavy duty washer 40 of a suitable composition or other packing material. As shown in FIGURE 1, the sealing washers 36 and 40 are dimensioned to contact the inner Wall of cylinder 10 whereas the washer 38 has a substantially smaller diameter so as to be spaced inwardly from the inner wall of cylinder 10. Accordingly, there is provided a space between flexible washer 40 and washer The piston head 20 is provided with a small port 42 extending longitudinally therethrough to provide for flow communication between the portions of chamber 15 on opposite sides of the piston head 20. The port 42 extends through all of the members comprising the piston head 20.

Spring means are provided for biasing the piston head 20 away from the cylinder head 12 to the position shown in FIGURE 1, which illustrates the position of the parts when the door is in a closed position. The spring means comprises a first spring 50 mounted in compression between the inner wall 52 of the cylinder head 12 and a spring holding washer 54 mounted for sliding movement on piston rod 24. The spring means also comprises a second spring 56 mounted in compression between spring holding washer 54 and the washer 40 of piston head 20. It will be apparent that the spring 50 biases the washer 54 away from cylinder head 12 and the spring 56 biases the piston head 20 away from washer 54 and cylinder head 12 by reason of the arrangement of the springs. The washer 54 is provided with a plurality of relatively large ports 55 to permit unrestricted flow of fluid therethrough.

Means are provided for oontroling the flow of fluid past the piston 20 during certain phases of the relative movement of the piston 20 and the cylinder 10. Such means comprises an annular washer 60 and a spring 62 positioned in compression between washer 54 and washer 60. By this arrangement the spring 62 biases washer 60 away from washer 54. The washer 60 is guided for reciprocal movement by contact with the inner wall of cylinder 10. The spring 62 is preferably connected at its ends to the washers 54 and 60. As shown in FIGURE 1, the spring 62 is shorter than spring 56 so that washer 60 is held in a position spaced from flexible washer 40.

It will be noted that the outer diameter of springs 50 and 62 are approximately the same as the internal diameter of cylinder wherefore the springs are held against any substantial transverse movement within cylinder 10. For the same reason the internal diameter of spring 56 is essen tially the same as the outer diameter of piston rod 24.

The manner in which the door check in accordance with the invention is installed in a doorway is shown in FIG- URE 4. The outside door 70, which may be as a screen or storm door, is hinged at 72 to a door frame 74. A suitable bracket 76 is fastened to the door jamb 78 and has the end 26 of the piston rod 24 pivotally connected thereto by a pivot pin 80 in accordance with conventional practice. A bracket 84 is fastened to the inside of the door 70 and is pivotally connected to the projection 16 of the cylinder head 14 by a pivot :pin 86 in accordance with conventional mounting procedures.

In the use of the door check in accordance with the invention, it will be apparent that if the door 70 is moved from the closed position to an open position, the cylinder 10 will be carried with the door 70 and since the piston 20 is held against movement by its pivotal mounting 80 on the door jam 78, the cylinder 10 will move relative to the piston. In FIGURES 5, 6 and 7 the relative movement between the piston and cylinder is illustrated schematically for the closed position, a door open 45 and a door open 90", respectively. It wil be apparent that if the door is moved from a closed position toward an open position, the cylinder head 12 moves closer to the piston 20 to there by increase the compression of the springs therebetween.

Referring to FIGURES l and 5, with the door in the closed position, the springs are in a state of relatively little, if any, compression. Since the spring 62 extends from washer 54 a lesser amount than spring 56, the washer 60 is held in a position spaced from washer 40. During the movement of the door to a 45 open position, the relative movement between the piston 20 and the cylinder 10 is such that the piston head 12 moves closer to the piston 20 to thereby force fluid in chamber 15 past the piston from left to right as viewed in the drawings. This flow of the oil causes the washer 40 to bend to the position illustrated in FIGURE 2 whereby the periphery of washer 40 is spaced substantially from the inner wall of the cylinder 10. Thus, there is a relatively large passageway for the flow of oil past the piston 20. Since the spring 56 is stronger than the spring 50, the former will compress a lesser amount as the parts are moved from the FIGURE 5 position to the FIGURE 6 position. The parts are so designed that at this 45 open position of the door, the parts desira bly will attain the positions illustrated in FIGURE 6 with the washer 60 having moved into contact with the washer 40. The spring 62 may be compressed at very small amount in this condition of the parts.

Further opening movement of the door beyond the 45 open position will increase the compression of the three spring 50, 56 and 62. As the spring 62 is compressed, it will force washer 60 toward backing washer 38. Since a portion of backing washer 38 is overlapped by a portion of washer 60, with a portion of washer 40 therebetween, the movement of washer 60 is restricted by backing washer 38 whereby the sealing engagement by the contacting portion of washers 40 and 60 is enhanced to thereby block a substantial portion of the flow of oil around washer 40. Thus, the washer 40 is flexed very little, if any, toward the right (as shown in FIGURE 3) so that the flow passageway around the periphery of washer 40 is substantially reduced. Thus, greater force is necessary to open the door beyond the 45 position. However, there is still some flow of fluid past the periphery of washer 40 by reason of seepage passed the periphery of washer 60 and between the contacting surfaces between washers 60 and 40. Of course, there will be flow through the restricted orifice 42 during this movement. When the door has been opened to the full 90 open position, the parts are in the condition 4 shown in FIGURE 7 with all of the springs being substantially completely compressed.

After the door has been opened to a position greater than 45 and is released, the three springs acts to force the cylinder 10 away from the piston 20, i.e. toward the left as viewed in the drawings. However, this movement is limited by the blocking action of the piston against the fluid within the chamber 15 by the usual dash-pot type of action. In other words, the fluid on the right side of the piston 20 retards the movement of the cylinder 10 to the left and the cylinder movement is permitted at a rate related to the rate of flow of fluid passed the piston 20. By reason of the very effective seal provided at the periphery of the piston 20 between the cylinder 10 and washers 36 and 40, there is very little, if any, flow around the periphery of the piston. It is noted that as the fluid tries to flow from right to left, it forces the washer 40 against washer 60 to thereby expand the same and increase the sealing action between the periphery of washer 40 and the inner wall of cylinder 10. A similar action occurs with sealing washer 36. Accordingly, the flow rate through the restricted orifice provided by port 42 essentially determines the rate of closing movement of the door from the open position to the 45 position.

As the door has closed farther, i.e. to a position less than 45, the washer moves away from the member 40 to thereby permit the washer 40 to flex to the left and permit a substantial rate of flow of fluid passed member 40. Accordingly, the door will close at a faster rate than that in the region above 45 It will be evident that by reason of the construction in accordance with the invention, it is possible for someone to open the door a desired amount and the door will close very gradually. Accordingly, a person may pass through the doorway with packages or other articles without a necessity for holding the door open manually. Furthermore, a person may achieve various lengths of door closing delay by opening the door various amounts. Thus, by opening the door a greater amount passed 45, one can achieve a proportional increase in delay time.

An advantage of the construction in accordance with the invention is that it can be readily adapted for use with present day constructions. There is required only a minimum of modification of present day door checks to incorporate the novel aspects of the invention. For example, by inserting the washer S4, spring 56, spring 62 and washer 60 between the end of the present spring and piston head is possible to adapt the present day door checks to incorporate the present invention. Also, the washers 38 and 40 would preferably be added to the piston construction and it may be necessary to provide a restricted orifice in the piston.

Also, while the form of the invention disclosed herein is adapted for use with a fluid such as oil, it will be apparent that the door check can be designed for use with air. It will also be apparent that various changes may be made in the construction and arrangement of parts without departing from the scope of the invention. For example, the mounting on the door may be reversed with the piston rod secured to the door and the cylinder secured in the doorway. Accordingly, it is not desired to be limited except as required by the following claims.

I claim:

1. A door check comprising a cylinder having a head at each end thereof, a piston mounted within said cylinder in relatively fluid tight relation therewith for relative reciprocating movement therein, a piston rod secured to said piston and extending through one of said cylinder heads, spring means biasing said piston toward the other of said cylinder heads, said cylinder and said piston rod being adapted for connection to a door and door frame in a manner to cause said cylinder to move in one direction relative to said piston and compress said spring means in response to the opening of the door, said spring means being operative with the door in an open position to cause said cylinder to move in the opposite direction relative to said piston to thereby close the door, means providing a passageway for the flow of fluid between opposite sides of said piston during said relative movement between said piston. and said cylinder, a flow controlling member movable from a normal position to a flow blocking position in which said member blocks flow through at least a portion of said passageway, means mounting said flow controlling member in said cylinder for movement from said normal position to said blocking position in response to a first relative movement between said piston and said cylinder in said door opening direction, said mounting means holding said flow controlling member in said blocking position during a second relative movement between said piston and said cylinder in either of said door opening or door closing directions, said mounting means for said flow controlling member including a spring member movably mounting said fiow controlling member within said cylinder to permit relative movement between said cylinder and said flow controlling member during said second relative movement between said piston and said cylinder, said second relative movement occurring in a region in which said door is opened an amount greater than the amount the door is open during said first relative movement.

2. A door check according to claim 1 in which said spring means includes a spring holding member, a first spring in compression between said one cylinder head and said holding member, and second spring in compression between said holding member and said piston, said mounting means for said flow controlling member being connected to said holding member.

3. A door check according to claim 2 wherein said mounting means for said flow controlling member includes a third spring mounted in compression between said holding member and said flow controlling member, said third spring normally extending from said holding member a shorter distance than said second spring.

4. A door check according to claim 3 wherein said second spring is stronger than said first spring.

5. A door check according to claim 1 wherein said piston comprises a flexible disc-like member cooperable with the inner wall of said cylinder to define a portion of said passageway and adapted to move away from said inner wall to increase the size of said passageway, said flow controlling member comprising a washer movable into contact with said disc-like member to block the passageway defined thereby.

6. A door check according to claim 5 wherein said passageway providing means includes a restricted orifice in said piston extending longitudinal therethrough, said restricted orifice being located to be clear of said flow controlling member in said blocking position thereof.

7. A door check according to claim 2 wherein said piston comprises a flexible disc-like member cooperable with the inner wall of said cylinder to define a portion of said passageway and adapted to move away from said inner Wall to increase the size of said passageway, said flow controlling mernber comprising a Washer movable into contact with said disc-like member to block the passageway defined thereby.

8. A door check according to claim 7 wherein said passageway providing means includes a restricted orifice in said piston extending longitudinal therethrough, said restricted orifice being located to be clear of said flow controlling member in said blocking position thereof.

9. A door check according to claim 7 wherein said mounting means for said flow controlling member in said blocking position thereof.

9. A door check according to claim 7 wherein said mounting means for said flow controlling member includes a third spring mounted in compression between said holding member and said flow controlling member, said third spring being shorter than said second spring.

10. A door check according to claim 9 wherein said second spring is stronger than said first spring.

References Cited UNITED STATES PATENTS 1,124,941 1/1915 Norton 16-57 2,421,595 6/1947 Brown 1666 3,158,894 12/1964 Quinn 1666 FOREIGN PATENTS 527,991 7/1956 Canada.

BOBBY R. GAY, Primary Examiner.

JAMES L. KOHNEN, Assistant Examiner. 

